The invention relates to a radial shaft seal ring.
A radial shaft seal ring of this type is known from British Pat. No. 906,366. The lip ring is made of an elastomeric material and is vulcanized directly onto the inwardly directed extension of the reinforcing ring. Under operating conditions, the lip ring is at rest and its sealing lip wipes along the surface of the sealed shaft. It is therefore extremely prone to wear and can be expected to have a reasonably good service life only if the shaft surface is free of appreciable roughness. The shaft therefore requires careful finishing and its fabrication entails costly machining operations.
German Pat. No. 16 75 397 relates to a lip ring which rotates with the shaft and which, by a sealing lip that acts in the radial direction, bears on an annular surface of the housing which extends perpendicularly to the axis of rotation. Good sealing action can be secured in this case only if lip ring and housing are aligned with each other in a highly precise manner which is difficult to accomplish in the presence of vibration. This is why shaft seals of this type have not come into wide use.